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Mirroring Gears

I think that mirrored gears are always "inverted" when put on the symmetrical point - but since some of them are already symmetrical in shape, the net result is an apparent copy of the mesh. 

So I made this monstrosity, and gone peeking on the .craft file. I have three identical gears - one pair is mirrored, the third is not. Let's compare:

Mirrored Gear 1:

PART
{
    part = GearFixed_4293761660
    partName = Part
    persistentId = 1351969621
    pos = -0.585137546,9.84321308,-0.150621384
    attPos = 0,0,0
    attPos0 = -0.585137546,-0.150621355,0.156786948
    rot = 0.00416839123,0.0108874142,0.130581394,0.991369128
    attRot = 0,0,0,1
    attRot0 = -0.698056281,0.100033544,0.08463642,0.703951299
    mir = 1,1,1
    symMethod = Mirror
    autostrutMode = ForceHeaviest
    rigidAttachment = False
    istg = -1
    resPri = 0
    dstg = 0
    sidx = -1
    sqor = -1
    sepI = -1
    attm = 1
    modCost = 0
    modMass = 0
    modSize = 0,0,0
    sym = GearFixed_4293761560
    srfN = srfAttach,Mark1Cockpit_4293781902

Mirrored Gear 2 (counter part):

PART
{
    part = GearFixed_4293761560
    partName = Part
    persistentId = 1350094561
    pos = 0.585137546,9.84321308,-0.150621444
    attPos = 0,0,0
    attPos0 = 0.585137546,-0.150621414,0.156786948
    rot = 0.130581379,0.991369128,0.00416839123,0.0108873807
    attRot = 0,0,0,1
    attRot0 = 0.0846364349,0.703951299,-0.698056281,0.100033514
    mir = 1,1,-1
    symMethod = Mirror
    autostrutMode = ForceHeaviest
    rigidAttachment = False
    istg = -1
    resPri = 0
    dstg = 0
    sidx = -1
    sqor = -1
    sepI = -1
    attm = 1
    modCost = 0
    modMass = 0
    modSize = 0,0,0
    sym = GearFixed_4293761660
    srfN = srfAttach,Mark1Cockpit_4293781902

And finally, the single gear:

PART
{
    part = GearFixed_4293760032
    partName = Part
    persistentId = 731760417
    pos = -0.090433903,9.84336376,2.865376
    attPos = 0,0,0
    attPos0 = -0.090433903,2.86537576,0.156636
    rot = -0.132891148,0.240856349,0.47938621,0.833377004
    attRot = 0,0,0,1
    attRot0 = -0.683254719,0.509288371,0.168666065,0.495318294
    mir = 1,1,-1
    symMethod = Mirror
    autostrutMode = ForceHeaviest
    rigidAttachment = False
    istg = -1
    resPri = 0
    dstg = 0
    sidx = -1
    sqor = -1
    sepI = -1
    attm = 1
    modCost = 0
    modMass = 0
    modSize = 0,0,0
    srfN = srfAttach,Mark1Cockpit_4293781902

——— 

My current conclusions (subject to change as more informed people gathers here!) is that the "symMethod" alone doesn't define a mirrored part, you need also to define the counterpart on the "sym" field.

The magic appears to be made my using the "mir" field, where you use a "-1"  to indicate the axis you wanna to invert. Apparently using the -1 on the third value invert the part the way we want on gears. Note the "pos" field - the first value is the X axis, negative numbers are "from the left", positive numbers are "to the right". Y is from the bottom to the top (see how all gears are on the same Y plane!), and Z is from back to the front (note how the third gear change the 3rd value relative to the first pair!).

Building a craft like that and playing with that numbers on the craft file will render some interesting information!